Background: Reduction of low-density lipoprotein cholesterol (LDL-C) is important for patients with a high risk for atherosclerotic events, such as patients with diabetes and other risk factors. Anagliptin was reported to reduce LDL-C for 12 weeks in phase III trials regardless of the use of statins, but it is uncertain whether this effect is common to other dipeptidylpeptidase-4 (DPP-4) inhibitors.
Methods: A multicenter, randomized, open-label, parallel-group trial was conducted to confirm the superiority of anagliptin to sitagliptin in terms of the primary endpoint of reduction of LDL-C for 52 weeks in patients with type 2 diabetes and atherosclerotic vascular lesions, as well as the non-inferiority of anagliptin to sitagliptin in terms of change in hemoglobin A1c (HbA1c). Patients are randomly assigned to receive anagliptin or sitagliptin at a ratio of 1:1, with those in the anagliptin group receiving anagliptin 100 mg orally twice per day and those in the sitagliptin group receiving sitagliptin 50 mg orally once per day. During the trial period, hypoglycemic agents and anti-dyslipidemia drugs should not be added and neither should their dosages be changed. A total sample size of 300 was estimated to provide a power of 0.8 with a two-sided alpha of 0.05 for LDL-C, considering a 30% dropout rate. Pre-specified factors for subgroup analyses are HbA1c, use of DPP-4 inhibitors, sex, body mass index, LDL-C, age, and the presence of treatment for existing ischemic heart disease.
Discussion: If anagliptin were to be shown to reduce LDL-C in patients with type 2 diabetes and atherosclerotic vascular lesions despite pre-existing statin treatment, more intensive cholesterol management would be appropriate.
Trial registration: Clinicaltrials.gov NCT02330406.
Keywords: Cardiovascular risk; DPP-4 inhibitors; Dyslipidemia; Low-density lipoprotein cholesterol; Type 2 diabetic patients.